aknewb1s’ blog

Its taken quite a while for me to break even on doing my own refills -- and drink a lot of fizzy water in the process. I wonder how things would be different for SC if their prices for refills weren't so hi.

#7 finished, and a milestone passed.  This refilling equipment has paid itself off.

Finished #6 and just refilled #5 and #6.

Only one freezer trip required this time.  I got ~700g into #5 and ~850g into #6.  The CO2 stopped going in both times on its own for both cylinders.  #6 is was in the freezer longer which is probably why I got more CO2 into it.

#5 -- empty!

I thought I'd share one more technique I use.  When filling, put your ear up against the donor tank as you open the valve.  That way you can hear the quietest of sounds of gas moving from the donor to the recipient bottle.

I'm still unable to fill the bottles in one shot.  I crack the valve open very slightly and eventually gas eventually just stops going into to the SC bottle no matter how far the valve is opened.  However, after trips to the freezer, the bottles can be completely filled.  My last filling for #5 & #6 required two freezer trips, but that probably could have been reduced to one if I'd just left them in the freezer longer.

On the first cycle you don't need to worry about overfilling.  Gas will stop transferring on its own.  After the freezer trip though, you do need to watch how much is going into the SC bottle.

Finished bottle #4.  18.8 grams per liter.

Finished bottle #3 today.  18.3 grams of CO2 per liter of water.

I refilled two more cylinders last night.  For both I got them about 50% full and no more CO2 would go in.  So I let them sit in the freezer for a bit and after trying a second time got them to 80% where I stopped.

I did learn that when you first start slowly filling them up, if the cylinder is not completely cold you probably haven't put much into it.  So don't be afraid to keep the air flowing until the cylinder is completely cold.  Then disconnect and weigh so you can see where you are in the refilling process.

I recently used the procedure here http://soadahclub.vox.com to refill my soda maker.  Why?

Economics -- I averaged 55 liters per SC cylinder.  Granted, it depends on how fizzy you want your water, but its advertised as 110 liters so I got half of what they advertise.  That's about $0.39 per liter.  Not cheap!  You can find commercial soda for that price.  By refilling my own cylinders, the price per liter drops to $0.027.  Less than three cents!

Yes, the up front costs are quite high.  $74!! for the adapter which is basically a hunk of metal with a special thread, $50 for a used 20lb cylinder, and $13 for the first refill, but it will pay for itself in the long run.  The break even is about 355 liters (about 6.5 SC cylinders).

A few comments on refilling:

If you have a regular CO2 tank, refill your SC cylinder upside down.  Yes, its hard, and you'll need some way of propping up the heavy 20lb cylinder, but you'll save yourself quite a bit of trouble.

The first time I tried refilling a cylinder right side up (but slightly tilted), no matter how slowly I started the process, after filling about 20%, no more CO2 would go in the SC cylinder.  I finally resorted to making frequent trips to the freezer and after cooling the SC cylinder I could get in a little more CO2.  My theory as to what happened is that filling right side up added a bunch of gas to the SC cylinder rather than liquid CO2.  Cooling converted the CO2 gas into CO2 liquid.  Refilling upside down has worked much better since again my theory is that you're guaranteed to be filling only with liquid so you can completely fill the SC cylinder.

I filled my first SC cylinders to 70% of capacity.  That gives me about 35 liters.

Good luck!